KR20160043191A - Fuctional antireflection film - Google Patents

Abstract

Provided is a functional antireflection film with excellent antireflection function. The functional antireflection film comprises: a substrate layer; and a coating layer formed on at least one surface of the substrate layer. The coating layer includes silicon-acrylate graft polymer which includes a light-hardening type (meta) ester based resin; inorganic nanoparticles; polyacrylate chains and silicon side chains; and an antireflection film which includes a cured composite including a solvent.

Description

{FUCTIONAL ANTIREFLECTION FILM}

Functional anti-reflection film.

When the display is exposed to various kinds of illumination and natural light, the contrast is deteriorated due to the invisibility of the image formed inside the display due to reflected light, which makes it difficult to view the screen. . For this reason, the demand for reflection prevention is becoming very strong. Further, in order to improve the visibility of the display, in addition to the antireflection function, various functionalities for reducing the moire phenomenon or the Newton ring phenomenon are being developed and studied. However, it is still difficult to design an antireflection film for preventing reflection and ensuring various functions without hindering optical characteristics such as light transmittance.

One embodiment of the present invention provides an antireflection film that simultaneously implements an excellent antireflection function and a Newtoning function without impairing optical properties.

In one embodiment of the invention, a substrate layer; And a coating layer formed on at least one side of the base layer, wherein the coating layer is formed of a photocurable (meth) acrylate resin; Inorganic nanoparticles; A silicon-acrylate graft polymer comprising a polyacrylate backbone and a silicon side chain; And an antireflection film comprising a cured product of a composition comprising a solvent.

The silicone-acrylate graft polymer may have a weight average molecular weight (Mw) of from about 1000 to about 2500.

The silicon-acrylate graft polymer may comprise about 10 to about 30 weight percent of the silicon side chain.

The silicon side chain of the silicone-acrylate graft polymer may be exposed to the surface of the coating layer.

The solvent may have a polarity index of about 5.0 or less.

The solvent may include at least one selected from the group consisting of benzene solvents, ketone solvents, alcohol solvents, and combinations thereof.

The photocurable (meth) acrylic ester resin may have a weight average molecular weight (Mw) of about 150 to about 300.

The inorganic nanoparticles may have an average particle size of about 30 nm to about 60 nm.

The inorganic nanoparticles may include at least one selected from the group consisting of silica particles, titania particles, zirconium oxide particles, and combinations thereof.

The inorganic nanoparticles may be surface-treated with a silane compound.

About 10% to about 50% of the total surface area of the inorganic nanoparticles can be surface treated with the silane compound.

Wherein the silane-based compound is at least one selected from the group consisting of 3-aminopropyltriethoxysilane (AOPTMS), methacryloxypropyltrimethoxysilane (MAPTMS), 3-methacryloxypropyltrimethoxysilane, . ≪ / RTI >

The composition may include from about 0.03% to about 0.1% by weight of the silicone-acrylate graft polymer.

The composition may comprise from about 50% to about 90% by weight of the solvent.

The cured product can be formed by photocuring the composition with a light energy of about 200 mJ to about 400 mJ.

Wherein the base layer comprises at least one selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), polypropylene .

The thickness of the substrate layer may be from about 25 [mu] m to about 200 [mu] m.

The thickness of the coating layer may be from about 90 nm to about 120 nm.

The base layer may further include an adhesive layer and a release film layer on one side of the base layer.

The antireflection film is applied to a display or the like to secure a Newton ring function while ensuring excellent optical characteristics and antireflection function.

1 schematically shows a cross section of an antireflection film according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art to which the invention pertains. Only. Like reference numerals refer to like elements throughout the specification.

In one embodiment of the invention, a substrate layer; And a coating layer formed on at least one side of the base layer, wherein the coating layer is formed of a photocurable (meth) acrylate resin; Inorganic nanoparticles; A silicon-acrylate graft polymer comprising a polyacrylate backbone and a silicon side chain; And an antireflection film comprising a cured product of a composition comprising a solvent.

In general, an antireflection film is a structure in which a coating layer having antireflection function is laminated on a substrate layer to prevent light incident on a touch screen panel of a display or the like from being reflected to reduce visibility.

On the other hand, in the display, when two different base materials existing in the inside of the display come into contact with each other during the touch, an iridescent ring called Newton ring can be generated due to interference of light due to air layer pressing. do. A separate film can be prepared. However, the separate film for preventing the Newton ring must be present in the same position as the antireflection film structurally inside the display, so that the two films can not be simultaneously exposed to the surface.

Therefore, the antireflection film according to the present invention can solve the above-described problems and ensure excellent functionality by including a single coating layer that simultaneously implements an antireflection function and a Newton ring prevention function.

FIG. 1 schematically shows a cross section of an anti-reflection film 100 according to an embodiment of the present invention. Referring to FIG. 1, the anti-reflection film 100 includes a base layer 10 and a coating layer 20 formed on at least one side of the base layer 10.

The coating layer 20 simultaneously implements an antireflection function and a Newton ring prevention function, and specifically includes a photocurable (meth) acrylate resin; Inorganic nanoparticles; A silicon-acrylate graft polymer having a silicon side chain grafted to a polyacrylate main chain; And a solvent, and more specifically may comprise a cured product of the composition.

The silicon-acrylate graft polymer is a grafted silicon side chain in the main chain of polyacrylate, and plays a role of improving the Newton ring preventing function. In addition, the coating layer includes a cured product of the composition, and the silicone-acrylate graft polymer functions as an additive that does not react even during the curing of the composition and maintains its shape.

Specifically, the silicone-acrylate graft polymer may have a weight average molecular weight of about 1000 to about 2500. Since the silicone-acrylate graft polymer has a weight average molecular weight in the above range, excellent Newtoning preventing function can be realized without chemically reacting with other components of the composition.

In addition, the silicone-acrylate graft polymer may comprise about 10 to about 30 wt% of the silicon side chain And may include, for example, from about 20 to about 30% by weight. The silicone-acrylate graft polymer may contain the silicon side chain in the above-described range to impart slipperiness to the surface of the coating layer by interacting with the solvent, thereby securing an excellent Newtoning function. If the silicon-acrylate graft polymer contains less than about 10% by weight of the silicon side chain, it may be difficult to realize the Newton ring function by imparting slipperiness to the surface of the coating layer.

The silicon side chain of the silicone-acrylate graft polymer may be exposed on the surface of the coating layer, thereby imparting slippery property and obtaining an excellent Newtoning prevention function. Specifically, the degree of exposure of the silicon-acrylate graft polymer to the surface can be controlled depending on the polarity of the solvent.

Specifically, the solvent may have a polarity index of about 5.0 or less. The 'Polarity index' generally indicates the degree of polarity of the solvent, and is a numerical value of polarity from 0 to 10 in nonpolarity. When the degree of polarity of the solvent satisfies the above range, the degree of exposure of the silicon-acrylate graft polymer to the surface of the coating layer can be controlled to ensure excellent slippery property and to maximize the Newton ring function.

The solvent may be selected from the group consisting of pentane, 1,1,2-trichlorotrifluoroethane, cyclopentane, heptane, hexane, iso-octane, octane, cyclohexane, and dichloromethane; Ethers such as tetrahydrofuran and 1,4-dioxane; Benzene solvents such as toluene, xylene, chlorobenzene and dichlorobenzene; Ketone solvents such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diethyl ketone, dipropyl ketone, and cyclohexanone; And solvents such as methanol, ethanol, isopropanol, and butanol.

Specifically, the solvent may include at least one selected from the group consisting of benzene solvents, ketone solvents and alcohols solvents, and combinations thereof. In this case, the silicone-acrylate graft polymer may be exposed on the surface of the coating layer And the Newton ring prevention function can be effectively improved.

More specifically, the solvent is a mixture of a benzene solvent, a ketone solvent, and an alcohol solvent, and the polarity index of the mixture may be 5.0 or less, thereby realizing an excellent Newtoning prevention function.

The antireflection film may contain a photocurable (meth) acrylic ester resin in order to realize excellent optical characteristics. Specifically, the photocurable (meth) acrylic ester resin may be in an oligomer form.

More specifically, the photocurable (meth) acrylic acid ester resin may have a weight average molecular weight of about 150 to about 300. Since the photocurable (meth) acrylic acid ester resin has a weight average molecular weight in the above range, it is possible to facilitate the photo-curing of the composition containing the inorganic nanoparticles together, and to realize a coating layer having an appropriate degree of curing.

The photocurable (meth) acrylic acid ester resin may be a polyhydric alcohol; Polycarboxylic acids and their anhydrides; And at least one selected from the group consisting of polyester (meth) acrylate, polysiloxane polyacrylate, polyurethane (meth) acrylate, polyol poly (meth) acrylate, and combinations thereof obtained by esterifying acrylic acid But is not limited thereto.

The composition for forming the coating layer may further comprise a crosslinkable monomer to ensure proper crosslinking density of the photocurable (meth) acrylic ester resin, and may contain an appropriate amount as required.

The crosslinkable monomer may be selected from the group consisting of ethylene glycol diacrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol hexa Acrylate, di (meth) acrylate of bisphenol A-diglycidyl ether, urethane (meth) acrylate, pentaerythritol tetra (meth) acrylate, glycerin tri But is not limited thereto.

The composition for forming the coating layer serves to improve dispersibility and transparency and may include inorganic nanoparticles. The inorganic nanoparticles may include at least one selected from the group consisting of silica particles, titania particles, zirconium oxide particles, and combinations thereof.

The average particle size of the inorganic nanoparticles may be about 30 nm to about 60 nm. When the average particle diameter of the inorganic nanoparticles satisfies the above range, the composition can be easily coated with a thickness suitable for causing optical interference, thereby minimizing the reflectance and securing an appropriate particle density of the coating layer formed of the composition. Physical properties can be shown.

The inorganic nanoparticles may be surface-treated with a silane compound. The inorganic nanoparticles can be chemically bonded to the photocurable (meth) acrylic ester resin through such surface treatment, and excellent dispersibility and durability can be realized.

Specifically, the inorganic nanoparticles may be surface-treated with a silane-based compound having a surface area of about 10% to about 50% of the surface area of the particles, and in this case, the composition may have a coating layer having uniform dispersibility and excellent transparency . Specifically, the silane-based compound is selected from the group consisting of 3-aminopropyltriethoxysilane (AOPTMS), methacryloxypropyltrimethoxysilane (MAPTMS), 3-methacryloxypropyltrimethoxysilane, And may include at least one selected. The inorganic nanoparticles are surface-treated with such a silane-based compound, whereby excellent dispersibility and durability can be realized, and optical properties such as transparency can be enhanced.

The composition includes the silicone-acrylate graft polymer as an additive for securing the Newtonian function, and may specifically include about 0.03 wt% to about 0.1 wt%. By including the silicon-acrylate graft polymer in the above range, it is possible to secure an excellent Newtoning preventing function without impairing the antireflection function. When the amount of the silicone-acrylate graft polymer is less than about 0.03% by weight, the Newton ring-inhibiting function is difficult to achieve. When the amount of the silicone-acrylate graft polymer is more than about 0.1% by weight, There is a fear that the bonding force of the components constituting the coating layer is lowered.

In addition, the composition may comprise from about 50% to about 90% by weight of the solvent. By including the solvent in the above range in the above range, the silicone-acrylate graft polymer can be exposed to the surface of the coating layer and the Newton ring-preventing function can be effectively improved.

Also, the composition may contain about 1 wt% to about 5 wt% of the photocurable (meth) acrylic ester resin. In addition, the composition may comprise from about 5% to about 45% by weight of the inorganic nanoparticles. By including the resin and the inorganic nanoparticles in the above-described range, excellent optical characteristics can be realized while improving the antireflection function and the Newton ring prevention function.

The composition is photo-curable and may further comprise a photoinitiator. When the composition further comprises a photoinitiator, the content thereof may be about 0.5 wt% to about 1 wt%.

The type of the photoinitiator is not particularly limited, and examples thereof include an? -Hydroxyketone compound, a phenylglyoxylate compound, a benzyldimethylketal compound, an? -Aminoketone compound, a monoacylphosphine ( MAPO) -based compound, a bisacylphosphine (BAPO) -based compound, a phosphine oxide-based compound, a metallocene-based compound, an iodonium salt, and combinations thereof.

The coating layer may include a cured product of the composition, specifically, a photo-cured product of the composition. At this time, the cured product may be formed by photo-curing the composition at a light energy of about 200 mJ to about 400 mJ. By curing the composition with the light energy in the above range, it is possible to secure an appropriate degree of curing for exhibiting excellent optical characteristics while improving antireflection function and Newton ring prevention function.

Referring to FIG. 1, the anti-reflection film 100 includes a base layer 10, and the coating layer 20 may be formed on one side of the base layer 10.

The base layer 10 is formed of a transparent film such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), polypropylene (PP) As a material. For example, the base layer 10 may include polyethylene terephthalate (PET). In this case, the coating layer is excellent in an ability to combine with the coating layer, thereby increasing mechanical properties.

The thickness of the substrate layer 10 may be about 25 [mu] m to about 200 [mu] m. When the base layer 10 has a thickness in the above range, it can serve as a support for securing excellent durability without deteriorating transparency.

The thickness of the coating layer 20 may be about 90 nm to about 120 nm. By having the thickness of the coating layer 20 within the above range, it is possible to simultaneously realize an excellent antireflection function and a Newton ring prevention function without deteriorating optical characteristics.

The antireflection film may further include an adhesive layer and a release film layer on one side of the substrate layer. Specifically, the antireflection film may be a structure in which a release film layer, an adhesive layer, a substrate layer, and a coating layer are sequentially laminated. In this case, the antireflection film is easy to flow, easily attached to the adherend after the release film layer is removed, and can be easily applied to a display device or the like.

When the antireflection film further comprises an adhesive layer on one side of the substrate layer, the adhesive layer may be formed of a transparent adhesive, for example, the adhesive may be an acrylic adhesive, a rubber adhesive, a silicone adhesive, And the like.

The antireflection film exhibits excellent optical characteristics while ensuring antireflection function and Newton ring prevention function. Specifically, the antireflection film has a reflectance of about 5% or less, for example, about 1.1% or less, for example, about 1% . The 'reflectance' is the ratio of the light reflected by the antireflection film without being transmitted through the antireflection film. The reflectance of the antireflection film satisfies the above range.

In addition, the antireflection film may have a light transmittance of about 90% or more, for example, about 95% or more. The antireflection film has a light transmittance in the above range, so that excellent optical characteristics and antireflection function can be realized at the same time.

Hereinafter, specific embodiments of the present invention will be described. However, the embodiments described below are only intended to illustrate or explain the present invention, and thus the present invention should not be limited thereto.

< Example  And Comparative Example >

Example  One

10% by weight of surface-treated silica particles with 18% of the total surface area by 3-aminopropyltriethoxysilane (AOPTMS), 1% by weight of a photocurable acrylate resin which is a mixture of polysiloxane polyacrylate and polyurethane (meth) , 0.94% by weight of a photoinitiator (Ciba Co., Irgacure-184) were mixed, and 88% by weight of a solvent having a polarity of 1.8, which is a mixture of a ketone solvent, a benzene solvent and an alcohol solvent, To prepare a composition for a coating layer. On the other hand, a polyethylene terephthalate (PET) base layer having a thickness of 50 탆 was prepared, the composition for the coating layer was coated on one surface of the base layer and cured with light energy of 300 mJ to prepare a coating layer having a thickness of 100 nm, .

Example  2

An antireflection film was prepared in the same manner as in Example 1 except that a solvent having a polarity of 7.3, which is a mixture of a ketone solvent, a benzene solvent and an alcohol solvent, was used.

Comparative Example  One

10.055% by weight of the surface-treated silica particles with 18% of the total surface area by 3-aminopropyltriethoxysilane (AOPTMS), a photocurable acrylate (or copolymer) of polysiloxane polyacrylate and urethane (meth) acrylate 1.005% by weight of resin, And 0.94% by weight of a photoinitiator (Irgacure-184, manufactured by Ciba Co.) were mixed and 88% by weight of a solvent having a polarity of 1.8, which is a mixture of a ketone solvent, a benzene solvent and an alcohol solvent, was mixed to prepare a composition for a coating layer. On the other hand, a polyethylene terephthalate (PET) base layer having a thickness of 50 탆 was prepared, the composition for the coating layer was coated on one surface of the base layer and cured with light energy of 300 mJ to prepare a coating layer having a thickness of 100 nm, .

division Inorganic nanoparticle Photocurable resin Silicone-acrylate graft polymer Photoinitiator menstruum content Polarity Example 1 10 One 0.06 0.94 88 1.8 Example 2 10 One 0.06 0.94 88 7.3 Comparative Example 1 10.055 1.005 0 0.94 88 1.8

Table 1 shows the content of each component contained in the composition for the coating layer of each of Examples and Comparative Examples in terms of% by weight.

<Evaluation>

Experimental Example  1: Measurement of reflectance

Samples having dimensions of width x length = 50 mm x 50 mm were prepared for the antireflection films of the examples and comparative examples, and the reflectance was measured using a transmission reflectance measuring instrument (KONICA MINOLTA, Spectrophotometer CM-5) Are shown in Table 2 below.

Experimental Example  2: Light transmittance  Measure

Samples having dimensions of width x length = 50 mm x 50 mm were prepared for the antireflection films of the examples and comparative examples, and the light transmittance was measured using a transmission reflectance measuring instrument (KONICA MINOLTA, Spectrophotometer CM-5) The results are shown in Table 2 below.

Experimental Example  3: Newton Rings  Measurement of prevention function

A sample having dimensions of 80 mm x 120 mm in width x length = 80 mm x 120 mm was prepared for the antireflection films of the Examples and Comparative Examples, and the time at which the Newton rings produced after pressing the sample on the polarizing film was measured through visual evaluation And the results are shown in Table 2 below.

division reflectivity[%] Light transmittance [%] Newton ring protection Example 1 0.98 95.25 2 sec Example 2 1.09 95.3 15 sec Comparative Example 1 1.17 95.35 Not removed

With reference to the results in Table 2 above, the antireflection films of Examples 1 and 2 simultaneously realize excellent antireflection function, optical property and Newton ring prevention function, while Comparative Example 1 is a silicon-acrylate graft It can be seen that the polymer does not contain the polymer as an additive and therefore does not function as a Newton ring preventing function.

100: Antireflection film
10: substrate layer
20: Coating layer

Claims (19)

A base layer; And a coating layer formed on at least one surface of the substrate layer,
Wherein the coating layer comprises a photocurable (meth) acrylic acid ester resin; Inorganic nanoparticles; A silicon-acrylate graft polymer comprising a polyacrylate backbone and a silicon side chain; And a cure of a composition comprising a solvent.
Antireflection film.
The method according to claim 1,
The silicone-acrylate graft polymer has a weight average molecular weight (Mw) of 1000 to 2500
Antireflection film.
The method according to claim 1,
Wherein the silicon-acrylate graft polymer comprises 10 to 30 wt% of the silicon side chain
Antireflection film.
The method according to claim 1,
The silicon side chain of the silicon-acrylate graft polymer is exposed on the surface of the coating layer
Antireflection film.
The method according to claim 1,
The solvent has a polarity index of 5.0 or less
Antireflection film.
The method according to claim 1,
Wherein the solvent comprises at least one selected from the group consisting of a benzene solvent, a ketone solvent, an alcohol solvent, and combinations thereof
Antireflection film.
The method according to claim 1,
The photocurable (meth) acrylic ester resin has a weight average molecular weight (Mw) of 150 to 300
Antireflection film.
The method according to claim 1,
The inorganic nanoparticles preferably have an average particle diameter of 30 nm to 60 nm
Antireflection film.
The method according to claim 1,
Wherein the inorganic nanoparticles include at least one selected from the group consisting of silica particles, titania particles, zirconium oxide particles, and combinations thereof
Antireflection film.
The method according to claim 1,
The inorganic nanoparticles may be surface treated with a silane compound
Antireflection film.
11. The method of claim 10,
Wherein 10% to 50% of the total surface area of the inorganic nanoparticles is surface-treated with the silane compound
Antireflection film.
11. The method of claim 10,
Wherein the silane-based compound is at least one selected from the group consisting of 3-aminopropyltriethoxysilane (AOPTMS), methacryloxypropyltrimethoxysilane (MAPTMS), 3-methacryloxypropyltrimethoxysilane, Containing
Antireflection film.
The method according to claim 1,
Wherein the composition comprises from 0.03% to 0.1% by weight of the silicone-acrylate graft polymer
Antireflection film.
The method according to claim 1,
Said composition comprising from 50% to 90% by weight of said solvent
Antireflection film.
The method according to claim 1,
The cured product is formed by photocuring the composition with a light energy of 200 mJ to 400 mJ
Antireflection film.
The method according to claim 1,
Wherein the substrate layer comprises at least one selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (PC), polypropylene (PP)
Antireflection film.
The method according to claim 1,
The base layer has a thickness of 25 to 200 mu m
Antireflection film.
The method according to claim 1,
The thickness of the coating layer is preferably from 90 nm to 120 nm
Antireflection film.
The method according to claim 1,
Further comprising an adhesive layer and a release film layer on one side of the substrate layer
Antireflection film.

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